Silver halide emulsions sensitized with tricarbocyanine dyes containing a 1-piperazinyl group

ABSTRACT

NOVEL TRICARBOCYANINE DYES ARE PROVIDED HAVING A 1PIPERAZINYL GROUP GROUP ATTACHED TOT HE MESO CARBON ATOM OF THE METHINE LINKAGE OF THE DYE. LIGHT SENSITIVE SILVER HALIDE GRAINS ARE SPECTRALLY SENSITIZED WITH THE TRICARBOCYANINE DYES OF THIS INVENTION.

United States Patent Ofice 3,623,881

Patented Nov 30, 1971 In accordance with one embodiment of this invention, 3,623,881

SILVER HALIDE EMULSIONS SENSITIZED WITH novel tricarbocyanine dyes are provided having a l-piperl d i t th TRICARBOCYANINE DYES CONTAINING A azlny group attache to the meso carbon a om of e methine linkage of the dye.

l-PIPERAZINYL GROUP Arthur Fnmia, Jr., Hilton, and Leslie G. s. Brooker, 5 In another .embodlfnent of thls 9 Rochester, N.Y., assignor t E t Kodak tive s1 ver halide grams are spectrally sensitized with a palm Rochester tricarbocyanine dye having a l-piperazinyl group attached No Drawing. Continuation-impart of application Ser No, to the meso carbon atom of the methine linkage of the 860,395, Sept. 23, 1969. This application Mar. 25, 1970, dye. The tricarbocyanine dyes of this invention are out- Ser. No. 22,708 10 standing spectral sensitizers for light sensitive silver halide Illt- G030 1/10 grains. These new dyes sensitize such emulsions over a U.S. Cl. 96-427 9 Claims broader wavelength range, as compared with the closest related cyanine dyes, of about from 560 to 850 m and even higher in some instances, with maximum sensitivities ABSTRACT OF THE DISCLOSURE generally ranging from about 730 to 800 m Further,

Novel tricarbocyanine dyes are provided having a l- P new 91355 of tricarbocyanine y are eslwciany i i l group group attached to the meso carbon cient sensitizers for the red and near infrared region of atom of the methine linkage of the dye. Light sensitive the Spectrum in g are characterized y a y silver halide grains are spectrally sensitized with the tri- 9 fog level in emulsions, both fresh and 0H incubacarbocyanine dyes of this invention. U011- The most useful tricarbocyanine dyes of this invention comprise first and second 5- or 6-membered nitrogen con- This application is a continuation-in-part of our cotaining heterocyclic nuclei of the type employed in cypending application Ser. No. 860,395 filed Sept. 23, 1969, anine dyes, said nuclei being joined together by a straight now abandoned. chain linkage containing seven methine groups, said dye This invention relates to tricarbocyanine dyes and to having a l-piperazinyl group attached to the meso carbon light sensitive silver halide grains spectrally sensitized atom of said linkage, Especially good results are obtained with tricarbocyanine dyes. When the carbon atoms of the two methine groups ad- It is well known that carbocyanine dyes containing an jacent the meso carbon atom of the methine linkage are amino group on the meso carbon atom are useful filter joined by an ethylene linkage; the l-piperazinyl group dyes and spectral sensitizers for photographic silver hais a 4-(10Wer)alkoxycarbonylpiperazin-l-yl group; and, lide emulsions. For example, in Kendall et al., US. Pat. each heterocyclic nucleus of the dye is selected from the No. 2,705,234, issued Mar. 29, 1955, and in Brooker et group consisting of a benzoxazole nucleus, a benzothial., US. Pat. No. 2,735,770, issued Feb. 1, 1956, a numazole nucleus, and a naphthothiazole nucleus. ber of carbocyanine dyes of the above type are described The preferred tricarbocyanine dyes of this invention and shown to extend the sensitivity of ordinary silver are represented by the following general formula:

l a H (|3 \(IJIEE; H O CH Z /C\ I -Zl Ri-1 'I(oH=oH m io=oH-oH=o r; oH=o ,=E 9

\Q/ halide emulsions up to a range of about from 530 to wherein m and n each represents a positive integer of 685 my This sensitivity range is satisfactory for some from 1 to 2; R and R each represents an alkyl group photographic uses, but insufficient for other uses such (including substituted alkyl groups) having 1 t 18 aras for red and infrared photographic applications. It bon atoms such as methyl, ethyl, propyl, isopr-opyl, butyl, would, therefore, be highly desirable to provide carbocyisobutyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, unanine dyes sensitize silver halide emulsions to longer decyl, dodecyl, tridecyl tetradecyl, pentadecyl, hexadecyl, Wavelength radiations, for example, substantially above heptadecyl, octadecyl, etc., preferably a lower alkyl group 700 m having 1 to 4 carbon atoms, and a substituted alkyl group It is accordingly, one object of this invention to prosuch as a hydroxyalkyl group such as vide tricarbocyanine dyes.

Another object of this invention is to provide light fi-hydroxyethyl, 'y-hydroxypropyl, fl-hydroxypropyl, 'y-hysensitive silver halide grains sensitized with tricarbodroxybutyl, w-hdroxybutyl, etc.,

cyanine dyes, an alkoxyalkyl group such as fi-methoxyethyl, p-ethoxy- A further object of this invention is to provide dyes ethyl, B-butoxyethyl, y-methoxypropyl, 'y-ethoxypropyl, which are effective spectral sensitizers for light sensitive w-methoxybutyl, w-ethoxybutyl and w-butoxybutyl, for silver halide. example,

Still another object of this invention is to provide silver a carboxyalkyl group such as carboxymethyl, [Si-carboxyhalide spectrally sensitized to infrared radiation. ethyl, -carboxypropyl, w-carboxybutyl, etc.,

Another object of this invention is to provide infrared a sulfoalkyl group such as fl-sulfoethyl, 'y-sulfopropyl, 'ysensitive silver halide emulsions which retain high sensisulfobutyl, w-sulfobutyl, etc., tivity to infrared radiation on storage. a sulfatoalkyl group such as ,B-sulfatoethyl, 'y-sulfatopro- Other objects of this invention will become apparent pyl, 'y-sulfatobutyl, w-sulfatobutyl, etc., from a consideration of this disclosure and the appended an alkanoyloxyalkyl group such as fl-acetoxyethyl, ,B-proclaims. pionyloxyethyl, p-butyryloxyethyl, 'y-acetoxypropyl, y-

propionyloxypropyl, w-acetoxybutyl, w-propionyloxybutyl, w-butyryloxybutyl, etc., and

an alkoxycarbonylalkyl group such as methoxycarbonylmethyl, fi-methoxycarbonylethyl, fl-ethoxycarbonylethyl, -methoxycarbonylpropyl, 'y-ethoxycarbonylpropyl, w-methoxycarbonylbutyl, w-ethoxycarbonylbutyl, etc.

or an aralkyl group, e.g., benzyl, phenethyl, etc.; an alkenyl group of from 2 to 4 carbon atoms, e.g., allyl, propenyl, l-butenyl, 2-butenyl; or any aryl group, e.g., naphthyl, tolyl, ethylphenyl, xylyl, methoxyphenyl, phenyl chlorophenyl, sulfophenyl or a carboxyphenyl group; R represents an alkyl or an aryl group, such as the groups described above for R and R with R preferably representing an alkoxycarbonyl group in which the alkoxy group contains from 1 to 12 carbon atoms, such as methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl, isopropoxycarbonyl, butoxycarbonyl, pentyloxycarbonyl, hexyloxycarbonyl, decyloxycarbonyl or dodecyloxycarbonyl; Q represents the atoms to complete an ethylene linkage which can be substituted with one, two or more suitable groups, such as an alkyl group having 1 to 4 carbon atoms such as methyl, ethyl, propyl, isopropyl and butyl, a halogen atom such as chlorine or bromine, or an alkoxy group having 1 to 4 carbon atoms, such as methoxy, ethoxy, propoxy, isopropoxy and butoxy, for example; X represents an acid anion, e.g., chloride, bromide, iodide, thiocyanate, sulfamate, perchlorate, p-toluenesulfonate, methyl sulfate, ethyl sulfate, etc. and can be included in R or R for example when R or R represents a sulfoalkyl or carboxyalkyl group; and, Z and Z each represents the non-metallic atoms required to complete a 5- to 6-membered nitrogen containing heterocyclic nucleus of the type employed in cyanine dyes, such as a thiazole nucleus (e.g., thiazole, 4-methylthiazole, 4-

phenylthiazole, S-methylthiazole, 5-phenylthiazole, 4,5 dimethylthiazole, 4,5 diphenylthiazole, 4 (Z-thienylthiazole), etc.),

a benzothiazole nucleus, (e.g., benzothiazole, 4-chlorobenzothiazole, S-chlorobenzothiazole, 6-chlorobenzothiazole, 7-chlorobenzothiazole, 4-methylbenzothiazole, 5 methylbenzothiazole, 6 methylbenzothiazole, 5- bromobenzothiazole, 6 bromobenzothiazole, 4 phenylbenzothiazole, 5-phenylbenzothiazole, 4-methoxybenzothiazole, S-methoxybenzothiazole, -methoxybenzothiazole, S-iodobenzothiazole, 6-iodobenzothiazole, 4- ethoxybenzothiazole, S-ethoxybenzothiazole, tetrahydrobenzothiazole, 5,6-dimethoxybenzothiazole, 5,6-dioxymethylenebenzothiazole, 5 hydroxybenzothiazole, 6-hydroxybenzothiazole, etc.),

a naphthothiazole nucleus (e.g., naphthol[2,1-d]thiazole, naphtho[1,2 d]thiazole, 5 methoxynaphtho[2,3-d] thiazole, 5 ethoxynaphthoIl,2-d]thiazole, 7-methoxynaphthol[2,l]thiazole, 8 methoxyna-phtho[2,1 d] thiazole, etc.),

a thionaphtheno-7,6', 4,5-thiazole nucleus (e.g., 4'-methoxythianaphtheno 7',6', 4,5-thiazole, etc.),

an oxazole nucleus (e.g., oxazole, 4-methyloxazole, 5-

methyloxazole, 4 phenyloxazole, 4,5-diphenyloxazole, 4-ethyloxazole, 4,5-dimethyloxazole, 5-phenyloxazole, etc.),

a benzoxazole nucleus (e.g., benzoxazole, S-chlorobenzoxazole, 5 methylbenzoxazole, 5 phenylbenzoxazole, 6-methylbenzoxazole, 5,6-dimethylbenzoxazole, 4,6-dimethylbenzoxazole, S-methoxybenzoxazole, 5- ethoxybenzoxazole, S-chlorobenzoxazole, 6-methoxybenzoxazole, S-hydroxybenzoxazole, 6-hydroxybenzoxazole, etc.)

a naphthoxazole nucleus (e.g., a-naphthoxazole, B-naphthoxazole, etc.),

a selenazole nucleus (e.g., 4-methylselenazole, 4-phenylselenazole, etc.),

a benzoselenazole nucleus (e.g., benzoselenazole, S-chlorobenzoselenazole, 5 methoxybenzoselenazole, 5- hydroxybenzoselcnuzole, tetrahydrobenzoselenuzolc, etc.),

a naphthoselenazole nucleus (e.g., a-naphthoselenazole,

fl-naphthoselenazole, etc.

a thiazoline nucleus (e.g., thiazoline, 4-methylthiazoline,

etc.),

a Z-pyridine nucleus (e.g., 2-pyridine, 5-methyl-2-pyridine,

etc.),

a 4-pyridine nucleus (e.g., 4-pyridine, 3-methyl-4-pyridine, etc.),

a Z-quinoline nucleus (e.g., 2-quinoline, 6-chloro-2-quinoline, 8-chloro-2-quinoline, 6-methoxy-2-quinoline, 8- hydroxy-Z-quinoline, etc.

a 4-quinoline nucleus (e.g., 4-quinoline, 6-methoxy-4- quinoline, 7-methyl-4-quinoline, 8-chloro-4-quino1ine, etc.),

a l-isoquinoline nucleus (e.g., l-isoquinoline, 3,4-dihydrol-isoquinoline, etc.),

a 3-isoquinoline nucleus (e.g., 3-isoquinoline, etc.),

a 3,3-dialkylindolenine nucleus (e.g., 3,3-dimethylindolenine, 5 nitro-3,3 dimethylindolenine, 6-nitro-3,3-dimethylindolenine, 5-cyano-3,3-dimethylindolenine, 6- cyano 3,3 dimethylindolenine, 3,3,5-trimethylindolenine, 3,3,7-trimethylindolenine, etc.

an imidazole nucleus (e.g., imidazole, l-methylimidazole,

l-ethylimidazole, l-butylimidazole, 1-methyl-4-phenylimidazole, l-methyl-4,S-dimethylimidazole, etc.),

a benzimidazole nucleus, (e.g., benzimidazole, 1-methylbenzimidazole, 1 phenyl 5,6-dichlorobenzimidazole, etc.),

a naphthimidazole nucleus (e.g., l-methyl a-naphthimidazole, l-ethyl-a-naphthimidazole, l-butyl-a-naphthimidazole, l phenyl tat-naphthimidazole, l-phenyl-[inaphthimidazole, 1 methyl 5 methoxy-u-naphthimidazole, etc.), and

a benzindole nucleus such as 1H-benz[e]ind0le, 3H

benz[f]indole, and 3H-benz[g]indole, for example.

When R represents an alkyl group it is preferably an alkyl group having 1 to 4 carbon atoms such as methyl, ethyl, propyl, isopropyl and butyl, for example. When R represents an alkoxycarbonyl group it is preferably an alkoxycarbonyl group having 2 to 5 carbon atoms such as methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl, isopropoxycarbonyl and butoxycarbonyl, for example.

The new tricarbocyanine dyes of the invention include symmetrical and unsymmetrical tricarbocyanine dyes. The dyes of the invention wherein R represents an alkoxycarbonyl group are especially useful as spectral sensitizers having a low fog level and are preferred dyes.

Symmetrical tricarbocyanine dye compounds of the invention in addition to those specifically described in Examples 19 below, and which are useful in the practice of this invention, include:

3,3 dimethyl 10,12-ethylene-11-(4-ethoxycarbonyll-piperazinyl)oxatricarbocyanine perchlorate.

3,3 dibutyl 10,12-ethylene-11(4-ethoxycarbonyl-lpiperazinyl)oxatricarbocyanine perchlorate.

3,3 diethyl 10,12-ethylene-11-(4-butoxycarbonyl-lpiperazinyl)oxatricarbocyanine perchlorate.

3,3 diethyl 10,12-ethylene-11-(4-propyl-1-piperazinyl)oxatricarbocyanine perchlorate.

3,3 diethyl 10,12 ethylene-11-(4-butyl-1-pipcrazinyl oxatricarbocyanine perchlorate.

3,3 diethyl -l0,12 ethylene-l1-(4-phenyl-l-piperazinyl)oxatricarbocyanine perchlorate.

3,3 diethyl 10,12 ethylene-ll(4-propyl-l-piperazinyl)thiatricarbocyanine perchlorate.

3,3 diethyl 10,12 ethylene-l1-(4-butyl-l-piperazinyl)thiatricarbocyanine perchlorate.

3,3 dimethyl 10,12 ethylene-11-(4-ethoxycarbonyll-piperazinyl)thiatricarbocyanine perchlorate.

3,3 dipropyl 10,12 ethylene-1l-(4-ethoxycarbonyll-piperazinyl )thiatricarbocyanine perchlorate.

3,3 dibutyl 10,12-ethylene-ll-(4-butoxyczu'bonyl-l pipeiazinyl thiatriczubocyanirie perchlorate.

3,3 diethyl 10,12 ethylene-11-(4-methyl-1-piperazinyl)selenatricarbocyanine perchlorate.

3,3' diethyl 10,12 ethylene-11-(4-ethoxycarbonyll-piperazinyl) selenatricarbocyanine perchlorate.

The following representative unsymmetrical tricarbocyanine dye compounds are useful in the practice of this invention:

3,3 diethyl 10,12 ethylene-11-(4-methyl-l-piperazinyl oxathiatricarbocyanine perchlorate.

3,3 dibutyl 10,12 ethylene-1l-(4-methyl-l-piperazinyl)oxathiatricarbocyanine perchlorate.

3 ethyl 3 butyl-10,12-ethylene-11-(4-methyl-lpiperazinyl)oxatricarbocyanine perchlorate.

3 ethyl 3 butyl-10,12-ethylene-1l-(4-methyl-lpiperazinyl)thiatricarbocyanine perchlorate.

3,3 diethyl 10,12 ethylene-1l-(4-phenyl-1-piperazinyl)oxathiatricarbocyanine perchlorate.

3,3 diethyl 10,12 ethylene-1l-(4-ethyl-l-piperazinyl) oxathiatricarbocyanine perchlorate.

3,3 diethyl 10,12 ethylene-11-(4-ethoxycarbonyll-piperazinyl)oxathiatricarbocyanine perchlorate.

3,3 dibutyl 10,12 ethylene-11-(4-ethoxycarbonyll-piperazinyl)oxathiatricarbocyanine perchlorate.

3,3 diethyl 10,12 ethylene-11-(4-methoxycarbonyll-piperazinyl)oxathiatricarbocyanine perchlorate.

3,3 diethyl 10,12 ethylene (4-butoxycarbonyl-1- piperazinyl) oxathiatricarbocyanine perchlorate.

3,3 diethyl 10,12 ethylene-11-(4-methyl-1-piperazinyl)oxaselenatricarbocyanine perchlorate.

3,3 diethyl 10,12 ethylene-11-(4-butyl-1-piperazinyl) oxaselenatricarbocyanine perchlorate.

3,3 diethyl 10,12 ethylene-l1(4-methyl-1-piperazinyl)selenathiatricarbocyanine perchlorate.

3,3 diethyl 10,12 ethylene-11-(4-ethoxycarbonyll-piperazinyl)oxaselenatricarbocyanine perchlorate.

3,3 diethyl 10,12 ethylene-11-(4-ethoxycarbonyl-1- piperazinyl)selenathiatricarbocyanine perchlorate.

Typical useful dyes which do not include an ethylene linkage between the carbon atoms of the two methine groups adjacent the meso carbon atom of the methine linkage of the dye include:

Anhydro 11 (4 ethoxycarbonylpiperazin-l-yl)-3,3- di(3 sulfopropyl)thiatricarbocyanine hydroxide, triethylamine salt,

11 (4 ethoxycarbonyl 1-piperazinyl)-3,3-diethyloxatricarbocyanine perchlorate,

3,3 diethyl 11 (4-phenyl-1-piperazinyl)oxathiatricarbocyanine perchlorate.

The symmetrical tricarbocyanine dyes of the invention can be conveniently prepared by condensing a nitrogen heterocyclic compound of the general formula:

of .9 R1N(=CH-OH);;;1C-OH=CHNR4R5 X wherein m, R X and Z are as previously defined, R represents a hydrogen atom or an acyl group, e.g., acetyl, propionyl, butyryl, benzoyl, etc., and R represents an aryl group, e.g., phenyl, a tolyl group, etc., with an enamine salt of the general formula:

(III) is reacted with one mole of an enamine salt having the Formula III to obtain a compound having the Formula IV below:

One mole of the compound of Formula IV can then be reacted with one mole of an intermediate having the Formula II but differing from the intermediate having the Formula II used to obtain a compound having the Formula IV to obtain an unsymmetrical tricarbocyanine dye included within the scope of Formula I. R R Q, X and Z in Formula IV have the meaning previously assigned to them.

Dyes which do not have an ethylene group linking the carbon atoms of the two methine groups adjacent the meso carbon atom of the methine linkage, are prepared by reacting 4-acetoxy-2-H-pyran-2,6(3H)dione with a compound of the formula:

wherein R X and Z have the meanings given above, R

represents an acyl group (e.g., acetyl) and R represents an aryl group (e.g., phenyl), to obtain an intermediate having the formula:

wherein m, R and Z have the meanings given above, and then reacting a compound of Formula VI with a compound of Formula VII:

wherein n, R Z, R and R have the meanings given above, to obtain a compound of the formula:

(VIII) (I? Compound VIII can then be hydrolyzed to obtain compound IX:

pylamine, triisopropylamine, etc., N,N-dialkylanilines such as N,N-dimethylaniline, N,N-diethylaniline, etc., N- alkylpiperidines such as N-methylpiperidine, N-ethylpiperidine, etc., at elevated temperatures and preferably at refluxing temperatures of the reaction mixtures. On chilling, the dye compounds separate from the mixtures and are purified by one or more extractions or recrystallizations with appropriate solvents. In the case of the symmetrical dyes the reactants can be employed with a small excess of one or the other, i.e., greater than the stoichiometrically calculated equivalents, but preferably in the ratio of approximately 2 moles (plus a substantial excess of about 10%) of a heterocyclic compound of Formula II to each mole of the enamine salt of Formula III. In the case of the unsymmetrical dyes the reactants are employed in molar equivalents. The heterocyclic intermediates represented by Formula II are well known substances, and methods for preparing these compounds are well known to the art. The preparation of representative enamine salts coming under Formula III are described hereinafter.

In the preparation of photographic emulsions, the new dyes of the invention are advantageously incorporated in the washed, finished silver halide emulsion and should, of course, be uniformly distributed throughout the emulsion. The methods of incorporating dyes in emulsions are relatively simple and well known to those skilled in the art of emulsion making. For example, it is convenient to add the dyes from solutions in appropriate solvents, in which case the solvent selected should be completely free from any deleterious effect on the ultimate light-sensitive materials. Methanol, isopropanol, pyridine, etc., alone or in admixtures, have proven satisfactory as solvents for the majority 'of our new dyes. The type of silver halide emulsions that can be sensitized with the new dyes include any of those prepared with hydrophilic colloids that are known to be satisfactory for dispersing silver halides, for example, emulsions comprising natural materials such as gelatin, albumin, agar-agar, gum arabic, alginic acid, etc. and hydrophilic synthetic resins such as polyvinyl alcohol, polyvinyl pyrrolidone, cellulose ethers, partially hydrolyzed cellulose acetate, and the like.

The concentration of the new dyes in the emulsion can vary widely, i.e., from about 5 to about 100 mgs. per liter of flowable emulsion. The specific concentration will vary according to the type of light-sensitive material in the emulsion and according to the effects desired. The suitable and most economical concentration for any given emulsion will be apparent to those skilled in the art upon making the tests and observations customarily used in the art of emulsion making. The emulsions are coated to advantage on any conventional photographic support materials such as paper, glass, cellulose acetate, cellulose acetatepropionate, cellulose nitrate, polystyrene, polyesters, polyamides, etc.

To prepare a gelatino-silver halide emulsion sensitized with one of the new dyes, the following procedure is satisfactory: a quantity of the dye is dissolved in a suitable solvent and a volume of this solution containing from 5 to 100 mgs. of dye is slowly added to about 1000 cc. of the gelatino-silver halide emulsion. With most of the new dyes, to 23 mgs. of dye per liter of emulsion suflice to produce the maximum sensitizing effect with the oridinary gelatino-silver halides including silver chloride, bromide, bromoiodide, chlorobromide, chlorobromoiodide, etc. emulsins. With fine-grain emulsions, which include most of the ordinary employed gelatino-silver chloride emulsions and the like, somewhat larger concentrations of dye may be necessary to secure optimum sensitizing effect. While the preceding has dealt with emulsions comprising gelatin, it will be understood that these remarks apply generally to any emulsions wherein part or all of the gelatin is substituted by another suitable hydrophilic colloid such as mentioned above.

The above statements are only illustrative and are not to be understood as limiting the invention in any sense, as it will be apparent that the new dyes can be incorporated by other methods in many of the photographic silver halide emulsions customarily employed in the art. For instance, the dyes can be incorporated by bathing a plate or film upon which an emulsion has been coated, in the solution of the dye in an appropriate solvent. Bathing methods, however, are not to be preferred ordinarily.

In addition to the utility described hereinbefore the new tricarbocyanine dye compounds of the invention are also useful in false-color or false-sensitized photographic color films such as those described, for example, in Hanson U.S. Pat. 2,763,549 or on pages 48, 62 and 63 of Photo Methods for Industry for May 1963. Insofar as false-color or false sensitized photographic color films are concerned, the dye compounds of the invention are particularly useful in the case of false-sensitized multicolor films containing an infrared sensitive layer.

Silver halide emulsions spectrally sensitized with dyes in accordance with this invention can comprise silver chloride, silver bromide, silver bromoiodide, silver chlorobromoiodide or mixtures thereof. Such emulsions can be coarse, medium or fine grain (or mixtures thereof) and can be prepared by any of the well-known procedures, e.g., single jet emulsions, double jet emulsions. Useful emulsions include Lippmann emulsions, ammoniacal emulsions, thiocyanate or thioether ripened emulsions such as those described in Nietz et al. U.S. Pat. 2,222,264, Illings- Worth U.S. Pat. 3,320,069, and McBride U.S. Pat. 3,271,- 157; or, cubic grain emulsions, such as those described by Kline and Moisar, Journal of Photographic Science, vol. 12, page 242 et seq., or Markocki, The Spectral Sensitization of Silver Bromide Emulsions on Different Crystallographic Faces, Journal of Photographic Science, vol. 13, 1965. Surface image emulsions can be used or internal image emulsions such as those described in Davey et al. U.S. Pat. 2,592,250; Lowe et a1. U.S. Pat. 3,206,313; Berriman et al. U.S. Pat. 3,367,778 and Bacon et al. Belgian Pat. 704,255. If desired, mixtures of surfaces and internal image emulsions can be used as described in Luckey et al. U.S. Pat. 2,996,382. Negative type emulsions can be used as well as direct positive emulsions such as those described in Leermakers U.S. Pat. 2,184,- 013; Kendall et al. U.S. Pat. 2,541,472; Berriman U.S. Pat. 3,367,778; Schouivenaars British Pat. 723,019; Illingsworth French Pat. 1,520,821; Ives U.S. Pat. 2,563,785; Knott et al. U.S. Pat. 2,456,953; and Land U.S. Pat. 2,861,885.

The silver halide emulsions spectrally sensitized with the dyes of this invention can be unwashed or washed to remove soluble salts. In the latter case the soluble salts can be removed by chill-setting and leaching or the emulsion can be coagulation washed, e.g., by the procedures described in Hewitson et al. U.S. Pat. 2,618,556; Yutzy et al. U.S. Pat. 2,614,928; Yackel U.S. Pat. 2,565,418; Hart et al. U.S. Pat. 3,241,969; and Waller et al. U.S. Pat. 2,489,341.

Photographic emulsions containing sensitizing dyes in accordance with this invention can be sensitized with chemical sensitizers, such as with reducing agents; sulfur, selenium or tellurium compounds; gold, platinum or palladium compounds; or combinations of these. Suitable chemical sensitization procedures are described in Shepard U.S. Pat. 1,623,499; Allen U.S. Pat. 2,399,083; McVeigh U.S. Pat. 3,297,447; and Dunn U.S. Pat. 3,297,446.

The spectrally sensitized silver halide emulsions of this invention can contain speed increasing compounds such as polyalkylene glycols, cationic surface active agents and thioethers orcombinations of these as described in Piper U.S. Pat. 2,886,437; Chechak U.S. Pat. 3,046,134; Carroll et al. U.S. Pat. 2,944,900; and Goffe U.S. Pat. 3,294,540.

Silver halide emulsions containing the sensitizing dyes of this invention can be protected against the production of fog and can be stabilized against loss of sensitivity during keeping. Suitable antifoggants and stabilizers, which can be used alone or in combination, include the thiazo- 9 lium salts described in Staud U.S. Pat. 2,131,038 and Allen U.S. Pat. 2,694,716; the azaindenes described in Piper U.S. Pat. 2,886,437 and Heimbach U.S. Pat. 2,444,- 605; the mercury salts described in Allen U.S. Pat. 2,728,- 663; the urazoles described in Anderson U.S. Pat. 3,287,- 135; the sulfocatechols described in Kennard U.S. Pat. 3,236,652; the oximes described in Carroll et al. British Pat. 623,448; nitron; nitroindazoles; the mercaptotetrazoles described in Kendall et al. U.S. Pat. 2,403,927; Kennard et al. U.S. Pat. 3,266,897 and Luckey et al. U.S. Pat. 3,397,987; the polyvalent metal salts described in Jones U.S. Pat. 2,839,405; the thiuronium salts described in Herz U.S. Pat. 3,220,839; and the palladium, platinum and gold salts described in Trivelli U.S. Pat. 2,566,263 and Damschroder U.S. Pat. 2,597,915.

Photographic elements including emulsions spectrally sensitized in accordance with this invention can contain incorporated developing agents such as hydroquinones, catechols, aminophenols, 3-pyrazolidones, ascorbic acid and its derivatives, reductones and phenylenediamines, or combinations of developing agents. The developing agents can be in a silver halide emulsion and/or in another suitable location in the photographic element. The developing agents can be added from suitable solvents or in the form of dispersions as described in Yackel U.S. Pat. 2,592,368 and Dunn et al. French Pat. 1,505,778.

Silver halide spectrally sensitized in accordance with the invention can be dispersed in colloids that can be hardened by various organic or inorganic hardeners, alone or incombination, such as the aldehydes, and blocked aldehydes, ketones, carboxylic and carbonic acid derivatives, sulfonate esters sulfonyl halides and vinyl sulfones, active halogen compounds, epoxy compounds, aziridines, active olefins, isocyanates, carbodiimides, mixed function hardeners and polymeric hardeners such as oxidized polysaccharides, e.g., dialdehyde star-ch, oxyguargum, etc.

Photographic emulsions spectrally sensitized with the sensitizing dyes hereof can contain various colloids alone or in combination as vehicles or binding agents. Suitable hydrophilic materials include both naturally-occurring substances such as proteins, for example, gelatin, gelatin derivatives, cellulose derivatives, polysaccharides such as dextran, gum arabic and the like; and synthetic polymeric substances such as Water soluble polyvinyl compounds, e.g., poly (vinylpyrrolidone) acrylamide polymers or other synthetic polymeric compounds such as dispersed vinyl compounds in latex form, and particularly those which increase the dimensional stability of the photographic materials. Suitable synthetic polymers include those described, for example, in U.S. Pats. 3,142, 568 of Nottorf, issued July 28, 1964; 3,193,386 of White, issued July 6, 1965; 3,062,674 of Houck, Smith and Yudelson, issued Nov. 6, 1962; 3,220,844 of Houck, Smith and Yudelson, issued Nov. 30, 1965; Ream and Fowler 3,287,289, issued Nov. 22, 1966; and Dykstra U.S. Patent 3,411,911; particularly effective are those water-insoluble polymers of alkyl acrylates and methacrylates, acrylic acid, sulfoalkyl acrylates or methacrylates, those which have cross linking sites which facilitate hardening or curing and those having recurring sulfobetaine units as described in Canadian patent 774,054.

Emulsions spectrally sensitized in accordance with this invention can be used in photographic elements which contain antistatic or conducting layers, such as layers that comprise soluble salts, e.g., chloride, nitrates, etc., evaporated metal layers, ionic polymers such as those described in Minsk U.S. Pats. 2,861,056 and 3,206,312 or insoluble inorganic salts such as those described in Trevoy U.S. Pat. 3,428,451.

Photographic emulsions containing the sensitizing dyes of the invention can be coated on a wide variety of supports. Typical supports include cellulose nitrate film, cellulose ester film, poly(vinyl acetal) film, polystyrene film, poly(ethylene terephthalate) film, polycarbonate film and related films or resinous materials, as well as glass, paper,

10 metal and the like. Typically, a flexible support is employed, especially a paper support, Which can be partially acetylated or coated with baryta and/or an alpha-olefin polymer, particularly a polymer of an alpha-olefin containing 2 to 10 carbon atoms such as polyethylene, polypropylene, ethylene-butene copolymers and the like.

Spectrally sensitized emulsions of the invention can contain plasticizers and lubricants such as polyalcohols, e.g., glycerin and diols of the type described in Milton U.S. Pat. 2,960,404; fatty acids or esters such as those described in Robijns U.S. Pat. 2,588,765 and Duane U.S. Pat. 3,121,060; and silicone resins such as those described in Du Pont British Pat. 955,061.

The photographic emulsions spectrally sensitized as described herein can contain surfactants such as saponin, anionic compounds such as the alkyl aryl sulfonates described in Baldsiefen U.S. Pat. 2,600,831 and amphoteric compounds such as those described in Ben-Ezra U.S. Pat. 3,133,816.

Photographic elements containing emulsion layers sensitized as described herein can contain matting agents such as starch, titanium dioxide, zinc oxide, silica polymeric beads including beads of the type described in Jelley et al. U.S. Pat. 2,992,101 and Lynn U.S. Pat. 2,701,245.

Spectrally sensitized emulsions of the invention can be utilized in photographic elements which contain brightening agents including stilbene, triazine, oxazole and coumarin brightening agents. Water soluble brightening agents can be used such as those described in Albers et a1. German Pat. 972,067 and McFall et al. U.S. Pat. 2,933,390 or dispersions of brighteners can be used such as those described in Jansen German Pat. 1,150,274 and Oetiker et al. U.S. Pat. 3,406,070.

Light sensitive photographic emulsion layers spectrally sensitized with the subject sensitizing dye can be used in photographic elements which contain light absorbing materials and filter dyes such as those described in Sawdey U.S. Pat. 3,253,921; Gaspar U.S. Pat. 2,274,782; Carroll et a1. U.S. Pat. 2,527,583 and VanCarnpen U.S. Pat. 2,956,- 879. If desired, the dyes can be mordanted, for example, as described in Milton and Jones U.S. Pat. 3,282,699.

The sensitizing dyes (and other emulsion addenda) can be added to the photographic emulsion from water solutions or suitable organic solvent solutions, for example with the procedure described in Collins et a1. U.S. Pat. 2,912,343; Owens et al. U.S. Patent 3,342,605; Audran US. Pat. 2,996,287 or Johnson et al. U.S. Pat. 3,425,835. The dyes can be dissolved separately or together, and the separate or combined solutions can be added to a silver halide emulsion, or a silver halide emulsion layer can be bathed in the solution of dye or dyes.

Photographic emulsions of this invention can be coated by various coating procedures including dip coating, air knife coating, curtain coating, or extrusion coating using hoppers of the type described in Beguin U.S. Pat. 2,681,- 294. If desired, two or more layers may be coated simultaneously by the procedures described in Russell U.S. Pat. 2,761,791 and Wynn British Pat. 837,095.

Emulsions spectrally sensitized as described herein are useful in colloid transfer processes such as described in Yackel et al. U.S. Pat. 2,716,059; silver salt diffusion transfer processes such as described in Rott US. Pat. 2,352,014, Land U.S. Pat. 2,543,181, Yackel U.S. Pat. 3,020,155 and Land U.S. Pat. 2,861,885; color image transfer processes such as described in Rogers U.S. Pats. 3,087,817; 3,185,- 567; and 2,983,606; Weyerts U.S. Pat. 3,253,915, Whitmore et a1. U.S. Pats. 3,227,550, 3,227,551 and 3,227,552; and Land U.S. Pats. 3,415,644, 3,415,645, 3,415,646 and imbi bition transfer processes as described in Minsk U.S. Pat. 2,882,156.

Photographic emulsions of this invention can be used in elements designed for recording print out images as described in Fallesen U.S. Pat. 2,369,449 or Bacon et al. Belgian Pat. 704,255; direct print images as described in Hunt U.S. Pat. 3,033,682 and McBride U.S. Pat. 3,287,-

1 1 137; elements designed for processing by heat as described in Sorensen et al. US. Pat. 3,152,904, 3M British Pat. 1,110,046, Stewart US. Pat. 3,312,550 and Colt US. Pat. 3,148,122; or, in elements designed for physical development such as those described in Agfa British Pat. 920,277 and Gilman et al. British Pat. 1,131,238.

Silver halide emulsions containing the sensitizing dyes of this invention can be used in elements designed for color photography, for example, elements containing color-forming couplers such as those described in Frolich et al. US. Pat. 2,376,679; Vittum et al. US. Pat. 2,322,- 027; Fierke et al. US. Pat. 2,801,171; Godowsky US. Pat. 2,698,794; Barr et al. US. Pat. 3,227,554 and Graham US. Pat. 3,046,129; or elements to be developed in solutions containing color-forming couplers such as those described in Mannes and Godowsky US. Pat. 2,252,718; Carroll et al. US. Pat. 2,592,243 and Schwan US. Pat. 2,950,970.

Exposed photographic emulsions of this invention can be processed by various methods including processing in alkaline solutions containing conventional developing agents such as hydroquinones, catechols, aminophenols, 3- pyrazolidones, phenylenediamines, ascorbic acid derivatives, hydroxylamines, hydrazines and the like; web processing such as described in Tregillus et al. US. Pat. 3,179,- 517; stabilization processing as described in Yackel et al. Stabilization Processing of Films and Papers, PSA Journal, vol. 16B, August 1950; monobath processing as described in Levy Combined Development and Fixation of Photographic Images with Monobaths, Phot. Sci. and Eng, vol. 2, No. 3, October 1958, and Barnes et al. US. Pat. 3,392,019. If desired, the photographic emulsions of this invention can be processed in hardening developers such as those described in Allen et al. US. Pat. 3,232,761; in roller transport processors such as those described in Russell US. Pat. 3,025,779; or by surface application processing as described in Example 3 of Kitze US. Pat. 3,418,132.

The silver halide emulsions spectrally sensitized by the dye combinations of this invention can be used for making lithographic printing plates such as by the colloid transfer of undeveloped and unhardened areas of an exposed and developed emulsion to a suitable support as described in Clark et al. US. Pat. 2,763,553; to provide a relief image as described in Woodward US. Pat. 3,402,045 or Spencer US. Pat. 3,053,658; or, to prepare a relief printing plate as described in Baxter et al. US. Pat. 3,271,150.

Other spectral sensitizing dyes can be used in addition to the dyes of this invention to confer additional sensitivity to the light sensitive silver halide emulsion of the photographic elements of the invention. For instance, additional spectral sensitization can be obtained by treating the emulsion with a solution of a sensitizing dye in an organic solvent or the dye may be added in the form of a dispersion as described in Owens et al. French Pat. 1,482,- 774. For optimum results, the dye may either be added to the emulsion as a final step or at some earlier stage. Such dyes are described, for example, in Brooker and White US. Pat. 2,526, 632, issued Oct. 24, 1950; Sprague US. Pat. 2,503,776, issued Apr. 11, 1950; Brooker et al. US. Pat. 2,493,748; and Taber et al. U.S. Pat. 3,384,486. Spectral sensitizers which can be used with the dyes hereof includes the cyanines, merocyanines, complex (tri or tetranuclear) merocyanines, complex (tri or tetranuclear) cyanines, holopolar cyanines, styryls, hemicyanines (e.g., enamine hemicyanines), oxonols and hemioxonols.

Dyes of the cyanine classes that are useful in combination with the present dyes may contain such basic nuclei as the thiazolines, oxazolines, pyrrolines, pyridines, oxazoles, thiazoles, selenazoles and imidazoles. Such nuclei may contain alky, alkylene, hydroxyalkyl, sulfoalkyl, carboxyalkyl, aminoalkyl, and enamine groups and may be fused to carbocyclic or heterocyclic ring systems either unsubstituted or substituted with halogen, phenyl, alkyl, haloalkyl, cyauo, or alkoxy groups. The dyes may be sym- 12 metrical or unsymmetrical and may contain alkyl, phenyl, enamine or heterocyclic substituents on the methine or polymethine chain.

The merocyanine dyes which are useful in combination with the dyes of this invention may contain the basic nuclei mentioned above as well as acid nuclei such as thiohydantoins, rhodanines, oxazolidenediones, thiazolidenediones, barbituric acids, thiazolineiones, and malononitrile. These acid nuclei may be substituted with alkyl, alkylene, phenyl, carboxyalkyl, sulfoalkyl, hydroxyalkyl, alkoxyalkyl, alkylamino groups, or heterocyclic nuclei. Combinations of these dyes may be used, if desired. In addition, supersensitizing addenda which do not absorb visible light may be included; for instance, ascorbic acid derivatives, azaindenes, cadmium salts, and organic sulfonic acids as described in McFall et al. US. Pat. 2,933,390 and Jones et al. US. Pat. 2,937,089. Particularly useful supersensitizers for the present dyes are the sulfonated polynuclear aromatic compounds, silver halide reducing agents, azaindenes or combinations thereof, described in Hiller et al. US. patent application Ser. No. 860,394 filed Sept. 23, 1969.

The following examples are included for a further understanding of the invention.

EXAMPLE 1 3,3-diethyl-10,12-ethylene-11-(4-methyl-1-piperazinyl) oxatricarbocyanine perchlorate 1 cyclopentylidene 4 methylpiperazinium perchlorate (1.3 g., 1 mol.), 2 (2 acetanilidovinyl) 3 ethylbenzoxazolium iodide (4.8 g., 2 mols.+10%) and triethylamine (1.5 ml., 2 mols.+10%) are dissolved in acetic anhydride (15 ml.) and heated at reflux, with stirring, for 10 minutes, turned into a beaker, let stand for 5 minutes at room temperature, collected crude dye on a filter and washed with ethanol. After two recrystallizations from cresol-methanol, the yield of purified dye is 0.2 g. (6%), MP. 267-268 C. with decomposition.

EXAMPLE 2 3,3'-diethyl-10,12-ethylene-11-(4-methyl-l-piperazinyl) 1 cyclopentylidene 4 methylpiperazinium perchlorate (1.3 g., 1 mol.), 2 (2 acetanilidovinyl) 3 ethylbenzothiazolium iodide (5.0 g., 2 mols.+10%) and triethylamine (1.5 ml., 2 mols.+10%) are dissolved in ethanol (30 ml.) and heated at reflux for 10 minutes. After cooling to room temperature, the solid is collected on a filter, washed with methanol and dried. After two 13 recrystallizations from cresol/methanol the yield of purified dye is 1.0 g. (31%), M.P. 261-262 C. with decomposition.

EXAMPLE 3 3,3'-diethyl-10,12-ethylene-1 1- (4-phenyl-l-piperazinyl) thiatricarbocyanine perchlorate 1 cyclopentylidene 4 phenylpiperazinium perchlo- 0 rate (1.6 g., 1 mol.), 2 (2 acetanilidovinyl) 3 ethylbenzothiazolium iodide (5.0 g., 2 mols.+l0%) and triethylamine (1.5 ml., 2 mols.+%) are dissolved in acetic anhydride m1.) and heated at reflux for 10 minutes (with stirring). The mixture is then stirred at room temperature for 10 minutes, and then the solid is collected on a filter. The crude dye is first extracted with hot methanol and then recrystallized once from N,N-dimethylacetamide/methanol. The yield of purified dye is 1.5 g. (43%), M.P. 266-267 C. with decomposition.

EXAMPLE 4 3, 3 diethy1-10,12-ethylene-1 l-(4-ethyl-1-piperaziny1) oxatricarbocyanine perchlorate EXAMPLE 5 3 ,3 '-diethy1-l 0, l2-ethylene-1 1-(4-ethyl-1-piperazinyl) thiatricarbocyanine perchlorate 1 cyclopentylidene 4 ethylpiperazinium perchlorate (1.4 g., 1 mol.), 2 (2 acetanilidovinyl) 3 ethylbenzothiazolium iodide (5.0 g., 2 mols.+l0%) and triethylamine (1.5 ml., 2 mols.-|10%) are dissolved in acetic anhydride (15 ml.) and heated at reflux, with stirring, for 10 minutes. After cooling at room temperature for 5 minutes, the solid is collected on a filter, washed with methanol and dried. After one recrystallization from methanol, the yield of purified dye is 0.7 g. (21% M.P. 243-244 C. with decomposition.

EXAMPLE 6 11- (4-ethoxycarbony1-l-piperazinyl) -3,3 '-diethyl-10, l2- ethyleneoxatricarbocyanine perchlorate l cyclopentylidene 4 ethoxycarbonylpiperazinium perchlorate (1.6 g., 1 mol.), 2 (2-acetanilidovinyl)-3- ethylbenzoxazolium iodide (4.8 g., 2 mols.+10%) and triethylarnine (1.5 ml., 2 mols.+l0%) are dissolved in N,N-dimethylacetamide (10 ml.) and heated at a gentle reflux, with stirring, for 10 minutes. Turned into a beaker and diluted up to 350 ml. with hot methanol. After chilling, the solid is collected on a filter, washed with methanol and dried. After one recrystallization from methanol, the yield of purified dye is 0.8 g. (24%), M.P. 247248 C. with decomposition.

EXAMPLE 7 11-(4-ethoxycarbonyl-1-piperazinyl)-3 ,3 -diethyl-10,12- ethylenethiatricarbocyanine perchlorate l-cyclopentylidene 4 ethoxycarbonylpiperazinium perchlorate 1.6 g., 1 mol.), 2 (2-acetanilidovinyl)-3- ethylbenzothiazolium iodide (5.0 g., 2 mols.+10%) and triethylamine (1.5 ml., 2 mols.+l0%) are dissolved in N,N-dimethylacetamide (15 ml.) and heated at a gentle reflux, with stirring, for 10 minutes. Turned into a beaker and diluted up to 350 ml. with hot methanol. After cooling at room temperature for 10 minutes, the solid is collected on a filter, washed with methanol and dried. After one recrystallization from N,N-dimethylacetamide/methanol the yield of purified dye is 1.9 g. (54%), M.P. 266267 C. with decomposition.

1 EXAMPLE 8 Anhydro-l1-(4-ethoxycarbonylpiperazin 1 yl)-l0,12- ethylene-3,3-di(3-sulfopropyl) thiatricarbocyanine hydroxide, triethylamine salt 1 cyclopenylidene 4 ethoxycarbonylpiperazinium perchlorate (1.6 g.), anhydro 2 (2-anilinovinyl)-3-(3- sulfopropyl)benzothiazolium hydroxide (4.0 g.), acetic anhydride (1.0 ml.) and triethylamine (4.2 ml.) are dissolved in N,N-dimethylacetamide ml.) and heated on a mantle to reflux with stirring. When reflux is reached, the mantle is turned off and stirring of the reaction mixture is continued for 2 to 3 minutes. The reaction mixture is then filtered without being cooled prior to filtering. The dye compound formed is collected on the filter and, after one recrystallization from methanol, the yield of purified dye is 1.6 g. (36%), M.P. 235-236 C. dec.

EXAMPLE 9 Anhydro-ll-(4-ethoxycarbonylpiperazin 1 yl)-10,12-

ethylene 3,3 bis(3-sulfopropyl) 5,6;5,6-dibenzothiatricarbocyanine hydroxide, triethylamine salt 0 OC Hs l-(S-anilinomethylene 2 phenyliminomethyl-1-cyclopentenyl) -4 ethoxycarbonylpiperazine (2.16 g.), anhydro 2 methyl 3 (3-sulfopropyl)naptho[2,3-d]- thiazolium hydroxide (3.31 g), acetic anhydride (1.0 ml.), and triethylamine (1.0 ml.) are dissolved in N,N- dimethylacetamide (15 ml.) and heated at a gentle reflux for 2 minutes. After cooling, the crude dye is collected on a filter and then recrystallized once from methanol containing triethylamine. The yield of purified dye is 0.9 g. (19% M.P. 263264 C. dec.

The dyes of the above examples are tested in a gelatin silver bromoiodide emulsion containing 0.77 mole percent iodide of the type described by Trivelli and Smith, Phot. Journal, 79, 330 (1939). The dyes, dissolved in suitable solvents, are added to separate portions of the emulsion at the concentrations indicated. After digestion at 52 C. for 10 minutes, the emulsions are coated at a coverage of 432 mg. of. silver per square foot on a cellulose acetate film support. A sample of each coating is exposed on an Eastman IB Sensitometer and to a wedge spectrograph, processed for 3 minutes in the following composition:

Developer G. N-methyl-p-aminophenol sulfate 2.0 Sodium sulfite (anhydrous) 90.0 Hydroquinone 8.0 Sodium carbonate (monohydrate) 52.5 Potassium bromide 5.0 Water to make 1.0 liter.

and then fixed, washed and dried. The sensitizing values obtained are shown in the following Table 1.

TABLE 1 Sensitization Dye concen- Dye of tration (g.) Type of Range Maximum Example mole silver emulsion (m (mg) 0.02 Br0moi0dide T0830 750 0.02 10. 700 to 850 800 0. 02 do 700 to 840. 790 0.02 do 590m s20 750 0. 02 .do. 700 to s50 800 0. 02 .do. 500 to 310..... 730 0. 02 do. 580 to 850..... 780 0.024 .(l0 680 to 840..." 700 0 025 do 0&0 to 830..-" 790 The following examples illustrate the preparation of certain enamine salts that are employed as intermediates in the preceding dye preparation examples.

EXAMPLE 10 1-cyclopentylidene-4-methylpiperazinium perchlorate l-methylpiperazinyl hydroperchlorate (20.1 g., 1 mol.) and cyclopentanone (10.1 g., 1 mol.+20%) are dissolved in ethanol ml.) and heated at reflux for 30 minutes. After cooling, the solid is collected on a filter, rinsed with ethanol and dried. The yield is 16.1 g. (60% M.P. -15 8 C.

EXAMPLE 11 1-cyclopentylidene-4-phenylpiperazinium perchlorate 1 6 5 mo on, H; 0 011,

17 18 EXAMPLE 12 EXAMPLE 15 l-ethoxycarbony1-4-ethylpiperazine 1-cyclopentylidene-4-ethoxycarbonylpiperazinium 0 CZHS perchlorate 111 O\ /O C2115 l I Ii H C CH 2 2 1120/ CHz N I l 0104 I H20 CH3 C2H5 g/ This compound is prepared in the manner described ll Moore, Boyle, and Thorn, J. Chem. Soc., 1929', page 39.

EXAMPLE 13 15 E CHg l-ethylplperazme' g 1-ethoxycarbonylpiperazine hydroperchlorate (25.9 g., 20 1 mol.), cyclopentanone (10.1 g., 1 mol.+20%) and 4 H CH2 drops of 1-ethoxycarbonylpiperazine are dissolved in H26 6 ethanol (50 ml.) and heated at reflux for 30 minutes. After N cooling, the solid is collected on a filter, rinsed with ethanol and dried. The yield is 21.3 g. (65%), M.P. 139- C2 5 141 C.

The invention has been described in detail with particular reference to preferred embodiments thereof, but, it will be understood that variations and modifications can be eflected Within the spirit and scope of the invention.

We claim:

1. A light-sensitive silver halide emulsion spectrally sensitized with a tricarbocyanine dye comprising first and 1-ethoxycarbonyl-4-ethylpiperazine (22.7 g.) is dissolved in 100 ml. of 5 N NaOH and heated at reflux, with stirring, for 4 hours. After cooling, the mixture is treated with cone. HCl until just acid. Neutralized With Na CO made basic with 50% NaOH and then extracted continuously with benzene for several days. Removed the benzene under reduced pressure and distilled the residue. The yield is 2.0 sgcond or 6 membered nitrogen containing heterocyclic (14% 40 nuclei of the type used in cyanine dyes, said nuclei being EXAMPLE 14 joined by a straight chain linkage containing seven methine groups; said dye having a l-piperazinyl group attached to 1-cyclopentyl1dene-4-ethylpiperazmium perchlorate the meso carbon atom of Said linkage.

2. A light-sensitive silver halide emulsion spectrally l sensitized with a tricarbocyanine dye comprising first and 40 second 5- or 6-membered nitrogen containing heterocyclic 2 C10 6 nuclei of the type used in cyanine dyes, said nuclei being H20 4 joined by a straight chain linkage containing seven methine \ig/ groups; said dye having a 4-(lower)alkoxycarbonylpiperazine-yl group attached to the meso carbon atom of said linkage; the two carbon atoms of the two methine H20 CH2 groups adjacent said meso carbon atom being linked by an ethylene group; and, said heterocyclic nuclei being selected from the group consisting of a benzoxazole To a chilled solution of l-ethylpiperazine (2,0 g 1 nucleus; a benzothiazole nucleus; and a naphthothiazole mol.) in ether (200 ml.) is added slowly 72% perchloric 1111016118- acid (3.0 ml.). Decanted and dissolved the residue in 3. A light-sensitive silver halide emulsion spectrally ethanol (25 ml.). Heated to reflux, added cyclopentanone sensitized with a dye having the formula:

(2.0 g., 1 mol.+excess) and refluxed for 2 minutes. After wherein m and n each represents a positive integer of from chilling, the solid is collected on a filter and dried. The 1 to 2; R and R each represents a member selected from yield is 4.7 g. (96%). After one recrystallization from the group consisting of an alkyl group having 1 to 18 car- N,N-dimethylacetamide/methanol, the M.P. is 240-241 bon atoms, an alkenyl group having from 2 to 4 carbon C. with decomposition. 75 atoms; and an aryl group; R represents a member selected from the group consisting of an alkyl group having 1 to 12 carbon atoms and an aryl group; Q represents an ethylene linkage; X represents an acid anion and Z and Z each represents the nonmetallic atoms required to complete a heterocyclic nucleus of the type used in cyanine dyes.

4. A light-sensitive silver halide emulsion spectrally sensitized with a dye as defined in claim 3 wherein Z and Z each represents the atoms to complete a nucleus selected from the group consisting of a benzothiazole nucleus, a benzoxazole nucleus and a naphthothiazole nucleus; R and R each represents an alkyl group having from 1 to 4 carbon atoms; and, R represents an alkoxycarbonyl group in which the alkoxy group contains from 1 to 4 carbon atoms.

5. A light-sensitive silver halide emulsion spectrally sensitized with a dye selected from the group consisting of 3,3-diethyl-10,12-ethylene-11-(4-methyl 1 piperazinyl) oxatricarbocyanine salt, 3,3'-diethyl-10,12-ethylene-11-(4- methyl-l-piperazinyl)thiatricarbocyanine salt, 3,3'-diethyl- 10,12-ethylene-l1-(4-phenyl 1 piperazinyl)thiatricarbocyanine salt, 3,3'-diethyl-10,12-ethy1ene-11 (4 ethyl 1- piperazinyl)-oxatricarbocyanine salt, 3,3-diethyl-10,12- ethylene-11-(4-ethyl 1 piperazinyl)thiatricarbocyanine salt, 11-(4-ethoxycarb0nyl-l-piperazinyl)-3,3' diethyl-lO, 12-ethyleneoxatricarbocyanine salt, ll-(4-ethoxycarbonyll-piperazinyl)-3,3'-diethyl 10,12 ethylenethiatricarbocyanine salt, anhydro 11 (4-ethoxycarbonylpiperazin-1- yl)-10,12-ethylene 3,3 di(3-sulfopropyl)thiatricarbocyanine hydroxide salt, and anhydro-l1-(4-ethoxycarbon- 20 ylpiperazin l-yl)-10,l2-ethylene-3,3'-bis(3-sulfopropyl)- 5,6;5',6-dibenzothiatricarbocyanine hydroxide salt.

6. A light-sensitive silver halide emulsion spectrally sensitized with anhydro-l1-(4-ethoxycarbonylpiperazin-lyl)-l0,12-ethylene 3,3 di(3-sulfopropyl)thiatricarbocyanine hydroxide salt.

7. A photographic element having coated thereon a light-sensitive silver halide emulsion as defined in claim 1.

8. A photographic element having coated thereon a light-sensitive silver halide emulsion as defined in claim 3.

9. A photographic element having coated thereon a light-sensitive silver halide emulsion as defined in claim 5.

References Cited UNITED STATES PATENTS 216,736 7/1939 White et al. 96-127 275,234 3/1955 Kendall et al. 96137 275,770 2/1956 Brooker et al. 96137 342,978 12/1969 Fumia et al 96-127 FOREIGN PATENTS 674,800 1/ 1966 Belgium.

J. TRAVIS BROWN, Primary Examiner U.S. Cl. X.R. 

